Field of the Invention
The present invention relates to an image pickup system, an image pickup apparatus, and a control method therefor, and in particular to a drive control technique for an image pickup system that is comprised of an image pickup apparatus such as a digital camera, and a light-emitting apparatus such as a flash built in or removably mounted on the image pickup apparatus.
Description of the Related Art
Some image pickup apparatuses such as digital cameras use a technique called bounce flash photography in which flash is directed onto a ceiling or the like, and a subject is irradiated with diffused light reflected from the ceiling or the like. In the bounce flash photography, a subject is indirectly illuminated, and hence the subject is rendered with soft light.
Examples of such image pickup apparatuses using the bounce flash photography include those which provide automatic radiating direction control (auto bounce drive control) in which an optimum radiating direction of flash is automatically determined to drive a flash. In the auto bounce drive, a radiating direction of flash from a light-emitting unit to a ceiling or the like is calculated and automatically set based on information about a distance to the ceiling or the like and information about a distance from a subject at the time of bounce flash photography.
In the auto bounce drive, to automatically determine a radiating angle of flash, a distance measurement is performed so as to obtain the distance information mentioned above, but a user wants to suspend the distance measurement in some cases, for example, when he or she wants to go back to normal shooting or switch to movie shooting.
There has been disclosed a technique in which, after the auto bounce drive is started by operating a plurality of operating buttons including a shutter release button, the auto bounce drive is suspended in response to the shutter release button being pressed halfway down, and the auto bounce drive is continued when the operating buttons are operated otherwise (see Japanese Laid-Open Patent Publication (Kokai) No. 2015-210427).
There has also been disclosed a technique in which a bounce position of a light-emitting unit is manually changed after the auto bounce drive is started, and when the bounce position is unsuitable for bounce flash photography, an auto bounce drive mode is canceled (see Japanese Laid-Open Patent Publication (Kokai) No. 2015-4803).
During the auto bounce drive, flash is radiated from a light-emitting unit for the purpose of distance measurement described above, and it is thus impossible to perform photometry and obtain AF parameters required for shooting. For this reason, a preparatory operation for shooting such as photometry or AF in response to, for example, a shutter release button being pressed halfway down, and shooting operations in response to, for example, the shutter release button being pressed all the way down are disabled during the auto bounce drive, and they are enabled after completion of the auto bounce drive.
However, according to Japanese Laid-Open Patent Publication (Kokai) No. 2015-210427 and Japanese Laid-Open Patent Publication (Kokai) No. 2015-4803, when suspending the auto bounce drive, it takes a relatively long time to mechanically stop it. For this reason, if the completion of a suspending process for the auto bounce drive is awaited, AF cannot be performed or the shutter release button cannot be operated, and hence the user risks missing the perfect moment to take a picture.